A great question came up in class this week:  "What's the maximum number of days that I can retain a deleted item for in SharePoint?"

I couldn't find a quick answer to this in my 2 minutes of online searching, so I thought I'd try it out.  Since I had my virtual environment up anyway, I tried setting the limit to one thousand trillion days (1000000000000000)...that's as far as the input box would let me go.  SharePoint then informed that the maximum number of days for stage 1 is 10,000 days and that the maximum number of days for stage 2 is 500.

As far as I know, this is true for both SharePoint 2007 and SharePoint 2010, but please correct me if that assumption (no, I haven't verified it) is incorrect.